Longkou- Tudui gold deposit in Haiyang city is one of the important typical gold deposits in the northeast margin of Jiaolai Basin. The gold deposit is located in a microuplift in the northeast margin of Jiaolai Basin, bounded by NE trending fault surface. The orebody is strictly controlled by fault structure, the main orebody is controlled by NE strike, the left lateral compression- torsional fault structure of SE tilting, and the thick orebody is formed in the extension and occurrence of the structure; the deposit is formed because of the alteration rock type gold deposit of middle and low temperature hydrothermal structure after magmatic period; the mineralization is concentrated in 119±10 Ma. The sulfur source in the ore- forming hydrothermal solution may come from the same or similar source area as the vein rock, and the sulfur and ore- forming materials in the surrounding rock Jingshan Group are extracted in the process of ascending mineralization. The metallogenic fluids in the gold metallogenic belt in the northeast margin of Jiaolai Basin are similar, all of which are magmatic water mixed with atmospheric water. The main metallogenic fluid is CO2- NaCl- H2O system with medium and high temperature and low salinity. The metallogenic stages are divided into hydrothermal stage and epigenetic stage. It is a post- magmatic hydrothermal structural altered rock type gold deposit.